<?php
/**
 * 2007-2017 PrestaShop
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * https://opensource.org/licenses/OSL-3.0
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@prestashop.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade PrestaShop to newer
 * versions in the future. If you wish to customize PrestaShop for your
 * needs please refer to http://www.prestashop.com for more information.
 *
 * @author    PrestaShop SA <contact@prestashop.com>
 * @copyright 2007-2017 PrestaShop SA
 * @license   https://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
 * International Registered Trademark & Property of PrestaShop SA
 */

class AttachmentControllerCore extends FrontController
{

    public function postProcess()
    {
        $a = new Attachment(Tools::getValue('id_attachment'), $this->context->language->id);
        if (!$a->id) {
            Tools::redirect('index.php');
        }

        Hook::exec('actionDownloadAttachment', array('attachment' => &$a));

        if (ob_get_level() && ob_get_length() > 0) {
            ob_end_clean();
        }

        header('Content-Transfer-Encoding: binary');
        header('Content-Type: '.$a->mime);
        header('Content-Length: '.filesize(_PS_DOWNLOAD_DIR_.$a->file));
        header('Content-Disposition: attachment; filename="'.utf8_decode($a->file_name).'"');
        @set_time_limit(0);
        self::readfileChunked(_PS_DOWNLOAD_DIR_.$a->file);        
        exit;
    }

    /**
     * @see   http://ca2.php.net/manual/en/function.readfile.php#54295
     */
    function readfileChunked($filename,$retbytes=true)
    {
        // how many bytes per chunk
        $chunksize = 1*(1024*1024);
        $buffer = '';
        $totalBytes = 0;

        $handle = fopen($filename, 'rb');
        if ($handle === false)
        {
            return false;
        }
        while (!feof($handle))
        {
            $buffer = fread($handle, $chunksize);
            echo $buffer;
            ob_flush();
            flush();
            if ($retbytes)
            {
                $totalBytes += strlen($buffer);
            }
        }
        $status = fclose($handle);
        if ($retbytes && $status)
        {
            // return num. bytes delivered like readfile() does.
            return $totalBytes;
        }
        return $status;
    }
    
}
